Files
gocryptotrader/exchanges/coinbasepro/coinbasepro_websocket.go
2019-08-09 15:46:24 +10:00

327 lines
8.5 KiB
Go

package coinbasepro
import (
"errors"
"fmt"
"net/http"
"strconv"
"time"
"github.com/gorilla/websocket"
"github.com/thrasher-corp/gocryptotrader/common"
"github.com/thrasher-corp/gocryptotrader/common/crypto"
"github.com/thrasher-corp/gocryptotrader/currency"
exchange "github.com/thrasher-corp/gocryptotrader/exchanges"
"github.com/thrasher-corp/gocryptotrader/exchanges/asset"
"github.com/thrasher-corp/gocryptotrader/exchanges/orderbook"
"github.com/thrasher-corp/gocryptotrader/exchanges/wshandler"
)
const (
coinbaseproWebsocketURL = "wss://ws-feed.pro.coinbase.com"
)
// WsConnect initiates a websocket connection
func (c *CoinbasePro) WsConnect() error {
if !c.Websocket.IsEnabled() || !c.IsEnabled() {
return errors.New(wshandler.WebsocketNotEnabled)
}
var dialer websocket.Dialer
err := c.WebsocketConn.Dial(&dialer, http.Header{})
if err != nil {
return err
}
c.GenerateDefaultSubscriptions()
go c.WsHandleData()
return nil
}
// WsHandleData handles read data from websocket connection
func (c *CoinbasePro) WsHandleData() {
c.Websocket.Wg.Add(1)
defer func() {
c.Websocket.Wg.Done()
}()
for {
select {
case <-c.Websocket.ShutdownC:
return
default:
resp, err := c.WebsocketConn.ReadMessage()
if err != nil {
c.Websocket.DataHandler <- err
return
}
c.Websocket.TrafficAlert <- struct{}{}
type MsgType struct {
Type string `json:"type"`
Sequence int64 `json:"sequence"`
ProductID string `json:"product_id"`
}
msgType := MsgType{}
err = common.JSONDecode(resp.Raw, &msgType)
if err != nil {
c.Websocket.DataHandler <- err
continue
}
if msgType.Type == "subscriptions" || msgType.Type == "heartbeat" {
continue
}
switch msgType.Type {
case "error":
c.Websocket.DataHandler <- errors.New(string(resp.Raw))
case "ticker":
ticker := WebsocketTicker{}
err := common.JSONDecode(resp.Raw, &ticker)
if err != nil {
c.Websocket.DataHandler <- err
continue
}
c.Websocket.DataHandler <- wshandler.TickerData{
Timestamp: ticker.Time,
Pair: currency.NewPairFromString(ticker.ProductID),
AssetType: asset.Spot,
Exchange: c.GetName(),
OpenPrice: ticker.Open24H,
HighPrice: ticker.High24H,
LowPrice: ticker.Low24H,
ClosePrice: ticker.Price,
Quantity: ticker.Volume24H,
}
case "snapshot":
snapshot := WebsocketOrderbookSnapshot{}
err := common.JSONDecode(resp.Raw, &snapshot)
if err != nil {
c.Websocket.DataHandler <- err
continue
}
err = c.ProcessSnapshot(&snapshot)
if err != nil {
c.Websocket.DataHandler <- err
continue
}
case "l2update":
update := WebsocketL2Update{}
err := common.JSONDecode(resp.Raw, &update)
if err != nil {
c.Websocket.DataHandler <- err
continue
}
err = c.ProcessUpdate(update)
if err != nil {
c.Websocket.DataHandler <- err
continue
}
case "received":
// We currently use l2update to calculate orderbook changes
received := WebsocketReceived{}
err := common.JSONDecode(resp.Raw, &received)
if err != nil {
c.Websocket.DataHandler <- err
continue
}
c.Websocket.DataHandler <- received
case "open":
// We currently use l2update to calculate orderbook changes
open := WebsocketOpen{}
err := common.JSONDecode(resp.Raw, &open)
if err != nil {
c.Websocket.DataHandler <- err
continue
}
c.Websocket.DataHandler <- open
case "done":
// We currently use l2update to calculate orderbook changes
done := WebsocketDone{}
err := common.JSONDecode(resp.Raw, &done)
if err != nil {
c.Websocket.DataHandler <- err
continue
}
c.Websocket.DataHandler <- done
case "change":
// We currently use l2update to calculate orderbook changes
change := WebsocketChange{}
err := common.JSONDecode(resp.Raw, &change)
if err != nil {
c.Websocket.DataHandler <- err
continue
}
c.Websocket.DataHandler <- change
case "activate":
// We currently use l2update to calculate orderbook changes
activate := WebsocketActivate{}
err := common.JSONDecode(resp.Raw, &activate)
if err != nil {
c.Websocket.DataHandler <- err
continue
}
c.Websocket.DataHandler <- activate
}
}
}
}
// ProcessSnapshot processes the initial orderbook snap shot
func (c *CoinbasePro) ProcessSnapshot(snapshot *WebsocketOrderbookSnapshot) error {
var base orderbook.Base
for _, bid := range snapshot.Bids {
price, err := strconv.ParseFloat(bid[0].(string), 64)
if err != nil {
return err
}
amount, err := strconv.ParseFloat(bid[1].(string), 64)
if err != nil {
return err
}
base.Bids = append(base.Bids,
orderbook.Item{Price: price, Amount: amount})
}
for _, ask := range snapshot.Asks {
price, err := strconv.ParseFloat(ask[0].(string), 64)
if err != nil {
return err
}
amount, err := strconv.ParseFloat(ask[1].(string), 64)
if err != nil {
return err
}
base.Asks = append(base.Asks,
orderbook.Item{Price: price, Amount: amount})
}
p := currency.NewPairFromString(snapshot.ProductID)
base.AssetType = asset.Spot
base.Pair = p
base.LastUpdated = time.Now()
err := c.Websocket.Orderbook.LoadSnapshot(&base, c.GetName(), false)
if err != nil {
return err
}
c.Websocket.DataHandler <- wshandler.WebsocketOrderbookUpdate{
Pair: p,
Asset: asset.Spot,
Exchange: c.GetName(),
}
return nil
}
// ProcessUpdate updates the orderbook local cache
func (c *CoinbasePro) ProcessUpdate(update WebsocketL2Update) error {
var Asks, Bids []orderbook.Item
for _, data := range update.Changes {
price, _ := strconv.ParseFloat(data[1].(string), 64)
volume, _ := strconv.ParseFloat(data[2].(string), 64)
if data[0].(string) == exchange.BuyOrderSide.ToLower().ToString() {
Bids = append(Bids, orderbook.Item{Price: price, Amount: volume})
} else {
Asks = append(Asks, orderbook.Item{Price: price, Amount: volume})
}
}
if len(Asks) == 0 && len(Bids) == 0 {
return errors.New("coibasepro_websocket.go error - no data in websocket update")
}
p := currency.NewPairFromString(update.ProductID)
err := c.Websocket.Orderbook.Update(Bids, Asks, p, time.Now(), c.GetName(), asset.Spot)
if err != nil {
return err
}
c.Websocket.DataHandler <- wshandler.WebsocketOrderbookUpdate{
Pair: p,
Asset: asset.Spot,
Exchange: c.GetName(),
}
return nil
}
// GenerateDefaultSubscriptions Adds default subscriptions to websocket to be handled by ManageSubscriptions()
func (c *CoinbasePro) GenerateDefaultSubscriptions() {
var channels = []string{"heartbeat", "level2", "ticker", "user"}
enabledCurrencies := c.GetEnabledPairs(asset.Spot)
var subscriptions []wshandler.WebsocketChannelSubscription
for i := range channels {
if (channels[i] == "user" || channels[i] == "full") && !c.GetAuthenticatedAPISupport(exchange.WebsocketAuthentication) {
continue
}
for j := range enabledCurrencies {
enabledCurrencies[j].Delimiter = "-"
subscriptions = append(subscriptions, wshandler.WebsocketChannelSubscription{
Channel: channels[i],
Currency: enabledCurrencies[j],
})
}
}
c.Websocket.SubscribeToChannels(subscriptions)
}
// Subscribe sends a websocket message to receive data from the channel
func (c *CoinbasePro) Subscribe(channelToSubscribe wshandler.WebsocketChannelSubscription) error {
subscribe := WebsocketSubscribe{
Type: "subscribe",
Channels: []WsChannels{
{
Name: channelToSubscribe.Channel,
ProductIDs: []string{
channelToSubscribe.Currency.String(),
},
},
},
}
if channelToSubscribe.Channel == "user" || channelToSubscribe.Channel == "full" {
n := fmt.Sprintf("%v", time.Now().Unix())
message := n + "GET" + "/users/self/verify"
hmac := crypto.GetHMAC(crypto.HashSHA256, []byte(message),
[]byte(c.API.Credentials.Secret))
subscribe.Signature = crypto.Base64Encode(hmac)
subscribe.Key = c.API.Credentials.Key
subscribe.Passphrase = c.API.Credentials.ClientID
subscribe.Timestamp = n
}
return c.WebsocketConn.SendMessage(subscribe)
}
// Unsubscribe sends a websocket message to stop receiving data from the channel
func (c *CoinbasePro) Unsubscribe(channelToSubscribe wshandler.WebsocketChannelSubscription) error {
subscribe := WebsocketSubscribe{
Type: "unsubscribe",
Channels: []WsChannels{
{
Name: channelToSubscribe.Channel,
ProductIDs: []string{
channelToSubscribe.Currency.String(),
},
},
},
}
return c.WebsocketConn.SendMessage(subscribe)
}